The effect of high pressure-low temperature treatment on physicochemical properties in milk.
This study was carried out to investigate the effect of high pressure-low temperature (HPLT) treatment on physicochemical properties and nutrients in milk. The milk was treated at 200 MPa and -4 degrees C for 10, 20, and 30 min. Protease and lipase activities of HPLT-treated milk were highly inactivated compared with that of raw milk. Among time treatments, the 30-min treatment showed the lowest activities compared with others. Absorbance of thiobarbituric acid increased with time in HLPT-treated milks; however, no difference was observed between the raw milk and milk treated for 10 min. The concentrations of short-chain fatty acids except C(4) in HPLT-treated milks increased with time. The total free amino acids in HPLT-treated milks were greater than that of the raw milk for the 30-min treatment. L-Ascorbic acid, niacin, and riboflavin in HPLT-treated milks were significantly lower compared with concentrations in raw milk. For color, the L-value of HPLT-treated milks was significantly lower than that of the raw milk; however, there was no difference in the a-value for 10 min and in the b-value at 20 min between the raw milk and the HPLT-treated milks.
Kim
H Y
HY
Department of Food Science and Technology, Sejong University, Seoul 143-747, Korea.
Kim
S H
SH
Choi
M J
MJ
Min
S G
SG
Kwak
H S
HS
D000818:Animals; D003080:Cold Temperature; D003116:Color; D005230:Fatty Acids, Nonesterified / Q000032:analysis; D005524:Food Technology; D006863:Hydrogen-Ion Concentration; D008049:Lipase / Q000378:metabolism; D008892:Milk / Q000737:chemistry* / Q000201:enzymology; D011312:Pressure; D013858:Thiobarbiturates / Q000032:analysis; D014783:Viscosity; D014815:Vitamins / Q000032:analysis
D005230:Fatty Acids, Nonesterified; D013858:Thiobarbiturates; D014815:Vitamins; D008049:Lipase; C029684:thiobarbituric acid